Q:
A: It means that it is kosher for use during the Passover holiday, in addition to being kosher for the rest of the year. Foods eaten during the Passover may not have a leavening agent of any sort (even accidentally); foods eaten during other parts of the year may have leavening such as yeast. The kosher seal does not mean it has been "blessed" in any way; it simply meets certain standards of processing.